Display device

ABSTRACT

A display device is provided. The display device includes an array substrate including a substrate and a first electrode having an opening, wherein the opening has an edge. The array substrate further includes a second electrode disposed over the first electrode and including a first finger portion having a first side and a second side opposite to the first side. The second electrode further includes a connection portion connecting the first finger portion at the edge, wherein the connection portion has a first concavity at the first side and a second concavity at the second side, and a length of the first concavity is greater than a length of the second concavity. The display device further includes an opposite substrate and a display medium.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority from, and is acontinuation application of U.S. patent application Ser. No. 14/665,086filed on Mar. 23, 2015, entitled “Display device”, which claims thebenefit of priority from Taiwan Application No. 103143616 filed on Dec.15, 2014 and the entirety of which is incorporated by reference herein.

BACKGROUND

1. Technical Field

The disclosure relates to a display device with an array substrate, andin particular to a display device with an electrode having a concavity.

2. Description of the Related Art

Display devices are becoming more widely used in the display elements ofvarious products. Liquid-crystal molecules have different lightpolarization or light refraction effects at different alignmentconfigurations, and liquid-crystal display devices utilize thischaracteristic to control light penetration to generate images.Conditional twisted nematic liquid-crystal display devices have goodlight penetration characteristics. However, they cannot provide asufficient viewing angle due to the structure and the opticalcharacteristics of the liquid-crystal molecules.

In order to solve this problem, various liquid-crystal display deviceswith wide-angles and high aperture ratios have been developed, such asan in-plane switching liquid-crystal display device or a fringe-fieldswitching liquid-crystal display device. However, in thoseliquid-crystal display devices, a few liquid-crystal molecules have analignment direction that is different from most liquid-crystalmolecules, which in turn decreases the liquid-crystal efficiency and thebrightness of the display panel when displaying images. In addition, thefew liquid-crystal molecules with the different alignment directionwould result dark stripe on the display screen. Alternatively, when thedisplay screen is subjected to an external force such as finger contact,the few liquid-crystal molecules with a different alignment directionwould result in an unnecessarily bright stripe on the display screen,which detracts from the quality of the display.

Therefore, a display device which may further decrease the amount of theliquid-crystal molecules with a different alignment direction is needed.

SUMMARY

The present disclosure provides a display device, including: an arraysubstrate, including: a substrate; a first electrode disposed over thesubstrate, wherein the first electrode has an opening and the openinghas an edge parallel to a gate-line-extending direction; and a secondelectrode disposed over the first electrode, wherein the secondelectrode includes: a first finger portion having a first side and asecond side opposite to the first side, wherein a first outer edge ofthe first finger portion intersects the gate-line-extending direction atan acute angle at the first side, and a second outer edge of the firstfinger portion intersects the gate-line-extending direction at an obtuseangle at the second side; and a connection portion connecting the firstfinger portion at the edge, wherein the connection portion has a firstwidth along the gate-line-extending direction adjacent to the edge, andthe connection portion has a second width along the gate-line-extendingdirection away from the edge, wherein the first width is smaller thanthe second width, wherein the connection portion has a first concavityat the first side and a second concavity at the second side, and alength of the first concavity is greater than a length of the secondconcavity; an opposite substrate; and a display medium disposed betweenthe array substrate and the opposite substrate.

The present disclosure also provides a display device, including: anarray substrate, including: a substrate; a first electrode disposed overthe substrate, wherein the first electrode has an opening and theopening has an edge parallel to a gate-line-extending direction; and asecond electrode disposed over the first electrode, wherein the secondelectrode includes: a first finger portion having a first side and asecond side opposite to the first side, wherein a first outer edge ofthe first finger portion intersects the gate-line-extending direction atan acute angle at the first side, and a second outer edge of the firstfinger portion intersects the gate-line-extending direction at an obtuseangle at the second side; and a connection portion connecting the firstfinger portion at the edge, wherein the connection portion has a firstwidth along the gate-line-extending direction adjacent to the edge, andthe connection portion has a second width along the gate-line-extendingdirection away from the edge, wherein the first width is smaller thanthe second width, wherein the connection portion has an first inflectionpoint at the first side and an second inflection point at the secondside, wherein a distance between the first inflection point and the edgeis greater than a distance between the second inflection point and theedge along a direction perpendicular to the gate-line-extendingdirection; an opposite substrate; and a display medium disposed betweenthe array substrate and the opposite substrate.

The present disclosure also provides a display device, including: anarray substrate, including: a substrate; a first electrode disposed overthe substrate, wherein the first electrode has an opening and theopening has an edge parallel to a gate-line-extending direction; and asecond electrode disposed over the first electrode, wherein the secondelectrode includes: a first finger portion having a first side and asecond side opposite to the first side, wherein a first outer edge ofthe first finger portion intersects the gate-line-extending direction atan acute angle at the first side, and a second outer edge of the firstfinger portion intersects the gate-line-extending direction at an obtuseangle at the second side; and a connection portion connecting the firstfinger portion at the edge, wherein the connection portion has a firstwidth along the gate-line-extending direction adjacent to the edge, andthe connection portion has a second width along the gate-line-extendingdirection away from the edge, wherein the first width is smaller thanthe second width, wherein the connection portion has a first concavityat the first side and a second concavity at the second side, wherein adistance between a most-concave point of the first concavity and theedge is greater than a distance between a most-concave point of thesecond concavity and the edge along a direction perpendicular to thegate-line-extending direction, an opposite substrate; and a displaymedium disposed between the array substrate and the opposite substrate.

A detailed description is given in the following embodiments withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure may be more fully understood by reading the subsequentdetailed description and examples with references made to theaccompanying drawings, wherein:

FIG. 1A is a top view of an array substrate in accordance with someembodiments of the present disclosure;

FIG. 1B is a cross-sectional view of an array substrate along line 1B-1Bin FIG. 1A in accordance with some embodiments of the presentdisclosure;

FIG. 2 is a partially enlarged figure of the array substrate in FIG. 1A;

FIG. 3A is a partially enlarged figure of the array substrate in FIG. 2;

FIG. 3B is a partially enlarged figure of the array substrate in FIG. 2;

FIG. 3C is a partially enlarged figure of the array substrate in FIG. 2;

FIG. 3D is a partially enlarged figure of the array substrate in FIG. 2;

FIG. 4 is a top view and a partially enlarged figure of an arraysubstrate in accordance with another embodiment of the presentdisclosure; and

FIG. 5 is a cross-sectional view of a display device in accordance withsome embodiments of the present disclosure.

DETAILED DESCRIPTION

The display device of the present disclosure is described in detail inthe following description. In the following detailed description, forpurposes of explanation, numerous specific details and embodiments areset forth in order to provide a thorough understanding of the presentdisclosure. The specific elements and configurations described in thefollowing detailed description are set forth in order to clearlydescribe the present disclosure. It will be apparent, however, that theexemplary embodiments set forth herein are used merely for the purposeof illustration, and the inventive concept may be embodied in variousforms without being limited to those exemplary embodiments. In addition,the drawings of different embodiments may use like and/or correspondingnumerals to denote like and/or corresponding elements in order toclearly describe the present disclosure. However, the use of like and/orcorresponding numerals in the drawings of different embodiments does notsuggest any correlation between different embodiments. In addition, inthis specification, expressions such as “first insulating bump disposedon/over a second material layer”, may indicate the direct contact of thefirst insulating bump and the second material layer, or it may indicatea non-contact state with one or more intermediate layers between thefirst insulating bump and the second material layer. In the abovesituation, the first insulating bump may not directly contact the secondmaterial layer.

It should be noted that the elements or devices in the drawings of thepresent disclosure may be present in any form or configuration known tothose skilled in the art. In addition, the expression “a layer overlyinganother layer”, “a layer is disposed above another layer”, “a layer isdisposed on another layer” and “a layer is disposed over another layer”may indicate that the layer directly contacts the other layer, or thatthe layer does not directly contact the other layer, there being one ormore intermediate layers disposed between the layer and the other layer.

In addition, in this specification, relative expressions are used. Forexample, “lower”, “bottom”, “higher” or “top” are used to describe theposition of one element relative to another. It should be appreciatedthat if a device is flipped upside down, an element that is “lower” willbecome an element that is “higher”.

The terms “about” and “substantially” typically mean+/−20% of the statedvalue, more typically +/−10% of the stated value, more typically +/−5%of the stated value, more typically +/−3% of the stated value, moretypically +/−2% of the stated value, more typically +/−1% of the statedvalue and even more typically +/−0.5% of the stated value. The statedvalue of the present disclosure is an approximate value. When there isno specific description, the stated value includes the meaning of“about” or “substantially”.

It should be understood that, although the terms first, second, thirdetc. may be used herein to describe various elements, components,regions, layers and/or sections, these elements, components, regions,layers and/or sections should not be limited by these terms. These termsare only used to distinguish one element, component, region, layer orsection from another region, layer or section. Thus, a first element,component, region, layer or section discussed below could be termed asecond element, component, region, layer or section without departingfrom the teachings of the present disclosure.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this disclosure belongs. It should be appreciated that,in each case, the term, which is defined in a commonly used dictionary,should be interpreted as having a meaning that conforms to the relativeskills and the background or the context of the present disclosure, andshould not be interpreted in an idealized or overly formal manner unlessso defined.

The embodiments of the present disclosure enlarge the concavity of thepixel electrode at specific side to decrease the amount ofliquid-crystal molecules having the alignment direction that isdifferent from most liquid-crystal molecules to increase theliquid-crystal efficiency and decrease the bright stripe and the darkstripe.

Referring to FIGS. 1A and 1B. FIG. 1A is a top view of an arraysubstrate 100 in accordance with some embodiments of the presentdisclosure, and FIG. 1B is a cross-sectional view of the array substrate100 along line 1B-1B in FIG. 1A. The array substrate 100 may be atransistor substrate with a transistor array, such as a thin filmtransistor substrate. In addition, as illustrated in FIG. 1A, the arraysubstrate 100 has a plurality of sub-pixels 102, and as illustrated inFIG. 1B, the array substrate 100 includes a substrate 104, a firstelectrode 106 disposed over the substrate 104 and a second electrode 108disposed over the first electrode 106. It should be noted that, asillustrated in FIG. 1B, the first electrode 106 and second electrode 108are disposed at different planes. Therefore, the first electrode 106 andsecond electrode 108 shown in FIG. 1A are projections of these twoelectrodes on the same plane.

In particular, the substrate 104 may include, but is not limited to, atransparent substrate, such as a glass substrate, a ceramic substrate, aplastic substrate, or any other suitable transparent substrate. Inaddition, the substrate 104 may further include a data line 110, a gateline 112 (shown in FIG. 1A, but not shown in FIG. 1B) and theaforementioned transistor (not shown). The data line 110 may provide thesource signal to the sub-pixels 102, and the gate line 112 may providethe scanning pulse signal to the sub-pixels 102 and control thesub-pixels 102 in coordination with the aforementioned source signal. Inaddition, the gate line 112 extends along direction A1, and thedirection A2 refers to a direction that is substantially perpendicularor orthogonal to the gate-line-extending direction A1.

In addition, the first electrode 106 and second electrode 108 mayindependently include, but are not limited to, a transparent conductivematerial such as indium tin oxide (ITO), tin oxide (TO), indium zincoxide (IZO), indium gallium zinc oxide (IGZO), indium tin zinc oxide(ITZO), antimony tin oxide (ATO), antimony zinc oxide (AZO), acombination thereof, or any other suitable transparent conductive oxidematerial. In the embodiment shown in FIG. 1B, the first electrode 106 isa common electrode, and the second electrode 108 is a pixel electrode.In addition, the first electrode 106 which serves as the commonelectrode is disposed in the entire region of the sub-pixels 102. Thefirst electrode 106 has an opening 120. An insulating layer 114 isdisposed between the first electrode 106 and second electrode 108 and isfilled into the opening 120 of the first electrode 106. The material ofthe insulating layer 114 may include, but is not limited to, siliconoxide, silicon nitride, silicon oxynitride, a combination thereof, orany other suitable material.

In addition, a through hole V is disposed in the region of theinsulating layer 114 corresponding to the opening 120. The secondelectrode 108, which serves as a pixel electrode, is electricallyconnected to the data line 110 (not shown) in the substrate 104 throughthe through hole V. In other words, as illustrated in the top view ofFIG. 1A, the through hole V is disposed in the opening 120. In addition,the insulating layer 114 may electrically insulate the first electrode106 from the second electrode 108, such that an electric capacity may beformed between the first electrode 106 and the second electrode 108.

FIG. 2 is a partially enlarged figure of one of the second electrode108, which serves as a pixel electrode, of the array substrate 100 inFIG. 1A. As illustrated in FIG. 2, the second electrode 108 serving as apixel electrode includes a first finger portion 116 and a connectionportion 118. In addition, the opening 120 has an edge 120S parallel to agate-line-extending direction A1. In particular, the edge 120S refers tothe edge of the opening 120 which is parallel to a gate-line-extendingdirection A1 and is closer to the first finger portion 116. Namely, theedge 120S is the bold line pointed by reference numeral 120S. Inaddition, the first finger portion 116 and the connection portion 118may connect to each other substantially at the edge 120S. In addition,the extension line 120E refers to the line which is parallel to agate-line-extending direction A1 and substantially overlaps with theedge 120S.

As illustrated in FIG. 2, the first finger portion 116 has a first sideS1 and a second side S2 opposite to the first side S1, and the firstouter edge 116E1 of the first finger portion 116 intersects thegate-line-extending direction A1 (for example the direction of theextension line 120E) at an acute angle θ1 at the first side S1, and thesecond outer edge 116E2 of the first finger portion 116 intersects thegate-line-extending direction A1 (for example the direction of theextension line 120E) at an obtuse angle θ2 at the second side S2. Inother words, the first side S1 refers to the side where the first outeredge 116E1 of the first finger portion 116 intersects thegate-line-extending direction A1 (for example the direction of theextension line 120E) at the acute angle θ1 at the connection part of thefirst finger portion 116 and the connection portion 118. The second sideS2 refers to the side where the second outer edge 116E2 of the firstfinger portion 116 intersects the gate-line-extending direction A1 (forexample the direction of the extension line 120E) at the obtuse angle θ2at the connection part of the first finger portion 116 and theconnection portion 118.

FIG. 3A is an enlarged figure of the connection portion 118 and aportion of the first finger portion 116 in FIG. 2; namely, FIG. 3A is anenlarged figure of the region 300 in FIG. 2. As illustrated in FIG. 3A,the connection portion 118 has a first width W1 along thegate-line-extending direction A1 adjacent to the edge 120S, and theconnection portion 118 has a second width W2 along thegate-line-extending direction A1 away from the edge 120S. In addition,the first width W1 is smaller than the second width W2.

In particular, the connection portion 118 includes an upper portion 126Tadjacent to the edge 120S and a lower portion 126B away from the edge120S. The upper portion 126T has a first width W1 along thegate-line-extending direction A1, and the lower portion 126B has asecond width W2 along the gate-line-extending direction A1.

The upper portion 126T and the lower portion 126B of the connectionportion 118 is defined as follows. The connection portion 118 has afirst concavity 122A at the first side S1 and a second concavity 122B atthe second side S2. The first concavity 122A has a first end point 124Aaway from the edge 120S, and the second concavity 122B also has a secondend point 124B away from the edge 120S. An extension line is made alongthe gate-line-extending direction A1 with respect to the end point whichis chosen from the first end point 124A and the second end point 124Band is farther away from the edge 120S. For example, the extension line124AE is made with respect to the first end point 124A which is fartheraway from the edge 120S in FIG. 3A, and the extension line 124AE isparallel to the gate-line-extending direction A1 and passes through thefirst end point 124A. The extension line (for example the extension line124AE) separates the connection portion 118 into two portions. Theportion which is closer to the edge 120S is the upper portion 126T, andthe portion which is farther away from the edge 120S is the lowerportion 126B.

In addition, the first width W1 is the width between the first concavity122A and the second concavity 122B at the upper portion 126T along thegate-line-extending direction A1, and the second width W2 is the widthbetween the opposite sides at the lower portion 126B along thegate-line-extending direction A1.

In addition, the first concavity 122A and the second concavity 122B ofthe connection portion 118 are disposed merely in the upper portion 126Tof the connection portion 118, and are not disposed in the lower portion126B of the connection portion 118.

Still referring to FIG. 3A, in the connection portion 118 of the presentdisclosure, the length L1 of the first concavity 122A (namely the lengthof the bold line labelled as the reference numeral L1 in FIG. 3A) isgreater than the length L2 of the second concavity 122B (namely thelength of the bold line labelled as the reference numeral L2 in FIG.3A). This feature may decrease the amount of the liquid-crystalmolecules having the alignment direction different from mostliquid-crystal molecules to increase the liquid-crystal efficiency anddecrease the brightness non-uniformity that deteriorates the displayquality.

In particular, the present disclosure defines the first side S1 as theside where the first outer edge 116E1 of the first finger portion 116intersects the gate-line-extending direction A1 (at the acute angle θ1at the connection part of the first finger portion 116 and theconnection portion 118. The applicant discovered that the portion of theconnection portion 118 at the first side S1 would make a portion of theliquid-crystal molecules at the first side S1 have an alignmentdirection different from most liquid-crystal molecules, which in turnresults the brightness non-uniformity of the display quality anddecreases the liquid-crystal efficiency. Since the length L1 of thefirst concavity 122A is greater than the length L2 of the secondconcavity 122B in the present disclosure, the area of the portion of theconnection portion 118 at the first side S1 may be substantiallydecreased. Therefore, the amount of the liquid-crystal molecules at thefirst side S1 which have the alignment direction different from mostliquid-crystal molecules may be decreased to increase the liquid-crystalefficiency and the brightness of the display panel when displayingimages. In addition, the brightness non-uniformity may be reduced toimprove the display quality. For example, in one embodiment, theliquid-crystal efficiency of the liquid-crystal molecules in the regioncorresponding to the first concavity 122A at the first side S1 may beincreased from about 20% to 23%.

In addition, in the connection portion 118 of the present disclosure,the distance D1 between the first end point 124A of the first concavity122A and the edge 120S is greater than the distance D2 between thesecond end point 124B of the second concavity 122B and the edge 120S.

In particular, in FIG. 3A, the extension line 124AE is the line which isparallel to the gate-line-extending direction A1 and passes through thefirst end point 124A. The distance D1 between the first end point 124Aand the edge 120S refers to the distance between the extension line124AE and the extension line 120E along the direction A2 which isperpendicular to the gate-line-extending direction A1. Similarly, theextension line 124BE is the line which is parallel to thegate-line-extending direction A1 and passes through the second end point124B. The distance D2 between the second end point 124B and the edge120S refers to the distance between the extension line 124BE and theextension line 120E along the direction A2 which is perpendicular to thegate-line-extending direction A1.

As illustrated in FIG. 3A, the distance D1 being greater than thedistance D2 means that the area of the portion of the connection portion118 at the first side S1 is smaller than the area of the portion of theconnection portion 118 at the second side S2. Therefore, the amount ofthe liquid-crystal molecules having the alignment direction differentfrom most liquid-crystal molecules may be decreased to increase theliquid-crystal efficiency and the brightness of the display panel whendisplaying images and decrease the brightness non-uniformity to improvethe display quality.

FIG. 3B shows the same connection portion 118 and the same portion ofthe first finger portion 116 as FIG. 3A. The connection portion 118 andthe portion of the first finger portion 116 is reproduced in FIG. 3B inorder to illustrate the technical features of the present disclosuremore clearly. As shown in FIG. 3B, the connection portion 118 has afirst inflection point 134A at the first side S1 and a second inflectionpoint 134B at the second side S2. The distance D3 between the firstinflection point 134A and the edge 120S is greater than the distance D4between the second inflection point 134B and the edge 120S along thedirection A2 which is perpendicular to the gate-line-extending directionA1. This feature may further decrease the amount of the liquid-crystalmolecules having the alignment direction different from mostliquid-crystal molecules to increase the liquid-crystal efficiency anddecrease the brightness non-uniformity that deteriorates the displayquality.

In particular, the inflection point is the point where the center ofcurvature which located at the concave side of the curve changes fromone side of the curve to the other side. Take the side of the connectionportion 118 at the first side S1 for example, the portion of this sidewhich is closer to the edge 120S has the first line segment 128A (namelythe bold line pointed by reference numeral 128A in FIG. 3B) which has aconcavity outward to the outer side S3 of the connection portion 118.The portion of this side which is farther away from the edge 120S hasthe second line segment 128B (namely the bold line pointed by referencenumeral 128B in FIG. 3B) which has a concavity inward to the inner sideS4 of the connection portion 118. The first line segment 128A and secondline segment 128B compose the line segment 128. The inner side S4 isopposite to the outer side S3. In other words, the inner side S4 andouter side S3 are the opposite sides of the line segment 128. Inaddition, the center of curvature is the centre of a circle which istangent to a point on the curve and has the same curvature radius withthis point. In other words, the center of curvature is the point derivedby extending from a point on the curve toward the concavity by thedistance of the curvature radius of that point and along the directionperpendicular to the tangent direction of that point.

As shown in FIG. 3B, the first line segment 128A and second line segment128B are both curve lines. The center of curvature of any point (forexample the center of curvature 130) on the first line segment 128A islocated at the outer side S3 of the first line segment 128A or linesegment 128, and the center of curvature of any point (for example thecenter of curvature 132) on the second line segment 128B is located atthe inner side S4 of the second line segment 128B or line segment 128.The point where the center of curvature of the side of the connectionportion 118 including line segment 128 changes from the outer side S3 tothe inner side S4 is the first inflection point 134A of this side. Inaddition, the first inflection point 134A is also the connection pointof the first line segment 128A and second line segment 128B. Similarly,the second inflection point 134B of the connection portion 118 at thesecond side S2 is defined by the same method.

In addition, the extension line 134AE is the line which is parallel tothe gate-line-extending direction A1 and passes through the firstinflection point 134A. The distance D3 between the first inflectionpoint 134A and the edge 120S is the distance between the extension line134AE and the extension line 120E along the direction A2 which isperpendicular to the gate-line-extending direction A1. Similarly, theextension line 134BE is the line which is parallel to thegate-line-extending direction A1 and passes through the secondinflection point 134B. The distance D4 between the second inflectionpoint 134B and the edge 120S is the distance between the extension line134BE and the extension line 120E along the direction A2 which isperpendicular to the gate-line-extending direction A1.

As illustrated in FIG. 3B, the distance D3 between the first inflectionpoint 134A of the connection portion 118 and the edge 120S being greaterthan the distance D4 between the second inflection point 134B and theedge 120S means that the area of the portion of the connection portion118 at the first side S1 is smaller than the area of the portion of theconnection portion 118 at the second side S2. Therefore, the amount ofthe liquid-crystal molecules having the alignment direction differentfrom most liquid-crystal molecules may be decreased to increase theliquid-crystal efficiency and the brightness of the display panel whendisplaying images and decrease the brightness non-uniformity to improvethe display quality.

FIG. 3C shows the same connection portion 118 and the same portion ofthe first finger portion 116 as FIGS. 3A and 3B. The connection portion118 and the portion of the first finger portion 116 is reproduced inFIG. 3C in order to illustrate the technical features of the presentdisclosure more clearly. As illustrated in FIG. 3C, the distance D5between a most-concave point 136A of the first concavity 122A of theconnection portion 118 and the edge 120S is greater than the distance D6between a most-concave point 136B of the second concavity 122B and theedge 120S along the direction A2 perpendicular to thegate-line-extending direction A1. This feature may further decrease theamount of the liquid-crystal molecules having the alignment directiondifferent from most liquid-crystal molecules to increase theliquid-crystal efficiency and decrease the brightness non-uniformity ofthe display quality.

In particular, the line segment 138A is the line between the first endpoint 124A which is away from the edge 120S in the first concavity 122Aand the top end point 139A which is adjacent to the edge 120S. Themost-concave point 136A of the first concavity 122A is the point on thefirst concavity 122A which is the greatest distance from the linesegment 138A along the direction perpendicular to the line segment 138A.Similarly, the line segment 138B is the line between the second endpoint 124B which is away from the edge 120S in the second concavity 122Band the top end point 139B which is adjacent to the edge 120S. Themost-concave point 136B of the second concavity 122B is the point on thesecond concavity 122B which has the greatest distance to the linesegment 138B along the direction perpendicular to the line segment 138B.

In addition, the extension line 136AE is the line which is parallel tothe gate-line-extending direction A1 and passes through the most-concavepoint 136A of the first concavity 122A. The distance D5 between themost-concave point 136A of the first concavity 122A and the edge 120Srefers to the distance between the extension line 136AE and theextension line 120E along the direction A2 which is perpendicular to thegate-line-extending direction A1. Similarly, the extension line 136BE isthe line which is parallel to the gate-line-extending direction A1 andpasses through the most-concave point 136B of the second concavity 122B.The distance D6 between the most-concave point 136B of the secondconcavity 122B and the edge 120S refers to the distance between theextension line 136BE and the extension line 120E along the direction A2which is perpendicular to the gate-line-extending direction A1.

As illustrated in FIG. 3C, the distance D5 between the most-concavepoint 136A of the first concavity 122A of the connection portion 118 andthe edge 120S being greater than the distance D6 between themost-concave point 136B of the second concavity 122B and the edge 120Smeans that the area of the portion of the connection portion 118 at thefirst side S1 is smaller than the area of the portion of the connectionportion 118 at the second side S2. Therefore, the amount of theliquid-crystal molecules having the alignment direction different frommost liquid-crystal molecules may be decreased to increase theliquid-crystal efficiency and the brightness of the display panel whendisplaying images and decrease the brightness non-uniformity to improvethe display quality.

FIG. 3D shows the same connection portion 118 and the same portion ofthe first finger portion 116 as FIGS. 3A, 3B and 3C. The connectionportion 118 and the portion of the first finger portion 116 isreproduced in FIG. 3D in order to illustrate the technical features ofthe present disclosure more clearly. As illustrated in FIG. 3D, theconnection portion 118 has a first margin 140A connecting the firstconcavity 122A at the first side S1 and a second margin 140B connectingthe second concavity 122B at the second side S2. With respect to thegate-line-extending direction A1, the absolute slope value of the firstmargin 140A is different from that of the second margin 140B. Inaddition, in one embodiment, the absolute slope value of the firstmargin 140A is smaller than that of the second margin 140B. This featuremay further decrease the amount of the liquid-crystal molecules havingthe alignment direction different from most liquid-crystal molecules toincrease the liquid-crystal efficiency and decrease the brightnessnon-uniformity of the display quality.

In the embodiment shown in FIG. 3D, the angle θ3 between the firstmargin 140A of the connection portion 118 and the gate-line-extendingdirection A1 is not 90 degrees, and the angle θ4 between the secondmargin 140B and the gate-line-extending direction A1 is also not 90degrees. The aforementioned absolute slope value of the first margin140A, the absolute slope value of the second margin 140B, angle θ3 andangle θ4 may be defined by the first margin 140A, the second margin 140Band any line parallel to the gate-line-extending direction A1 (forexample the extension line A1E).

In particular, the extension line 140AE of the first margin 140Aintersects the extension line A1E at an intersection point 142A. Theline 144AE refers to the line which is parallel to the direction A2 andpasses through a point 144A on the extension line 140AE. The line 144AEintersects the extension line A1E at an intersection point 146A. Thedistance between the intersection point 146A and the intersection point142A is the distance X1, and the distance between the intersection point146A and the point 144A is the distance Y1. The aforementioned absoluteslope value of the first margin 140A with respect to thegate-line-extending direction A1 is the value derived by dividing thedistance Y1 by the distance X1 (namely Y1/X1).

Similarly, the extension line 140BE of the second margin 140B intersectsthe extension line A1E at an intersection point 142B. The line 144BErefers to the line which is parallel to the direction A2 and passesthrough a point 144B on the extension line 140BE. The line 144BEintersects the extension line A1E at an intersection point 146B. Thedistance between the intersection point 146B and the intersection point142B is the distance X2, and the distance between the intersection point146B and the point 144B is the distance Y2. The aforementioned absoluteslope value of the second margin 140B with respect to thegate-line-extending direction A1 is the value derived by dividing thedistance Y2 by the distance X2 (namely Y2/X2).

In addition, the angle θ3 refers to the acute angle between the firstmargin 140A (or the extension line 140AE thereof) and thegate-line-extending direction A1. The angle θ4 refers to the acute anglebetween the second margin 140B (or the extension line 140BE thereof) andthe gate-line-extending direction A1. Since the absolute slope value ofthe first margin 140A of the connection portion 118 is smaller than thatof the second margin 140B, the angle θ4 is greater than the angle θ3.

As shown in FIG. 3D, the absolute slope value of the first margin 140Aof the connection portion 118 being smaller than that of the secondmargin 140B (or the angle θ4 being greater than the angle θ3) means thatthe area of the portion of the connection portion 118 at the first sideS1 is smaller than the area of the portion of the connection portion 118at the second side S2. Therefore, the amount of the liquid-crystalmolecules having the alignment direction different from mostliquid-crystal molecules may be decreased to increase the liquid-crystalefficiency and the brightness of the display panel when displayingimages and decrease the brightness non-uniformity to improve the displayquality.

In addition, still referring to FIG. 3D, the length L3 of the firstmargin 140A (namely the length of the bold line labelled as thereference numeral L3 in FIG. 3D) may be smaller than the length L4 ofthe second margin 140B (namely the length of the bold line labelled asthe reference numeral L4 in FIG. 3D), this means that the area of theportion of the connection portion 118 at the first side S1 is smallerthan the area of the portion of the connection portion 118 at the secondside S2. Therefore, the amount of the liquid-crystal molecules havingthe alignment direction different from most liquid-crystal molecules maybe decreased to increase the liquid-crystal efficiency and thebrightness of the display panel when displaying images and decrease thebrightness non-uniformity to improve the display quality.

Next, still referring to FIG. 3D, the opening 120 of the first electrode106 (serving as a common electrode in this embodiment) has a first sideedge 148A at the first side S1 and a second side edge 148B at the secondside S2. The connection portion 118 of the second electrode 108 (serveas a pixel electrode in this embodiment) has a first region 150A outsidethe first side edge 148A (namely outside the bold line pointed byreference numeral 148A in FIG. 3D). The connection portion 118 has asecond region 150B outside the second side edge 148B has a second region150B outside the second side edge 148B (namely outside the bold linepointed by reference numeral 148B in FIG. 3D). The first region 150A hasa smaller area than the second region 150B.

In particular, the portion of the connection portion 118 which does notoverlap with the opening 120 may be divided into two portions. Theportion adjacent to the first side S1 is located outside the first sideedge 148A of the opening 120 and is referred to as the first region 150A(closer to the left side of the figure). The portion adjacent to thesecond side S2 is located outside the second side edge 148B of theopening 120 and is referred to as the second region 150B (closer to theright side of the figure).

As illustrated in FIG. 3D, since the first region 150A of connectionportion 118 which is closer to the first side S1 has a smaller area thanthe second region 150B which is closer to the second side S2, the amountof the liquid-crystal molecules having the alignment direction differentfrom most liquid-crystal molecules may be decreased to increase theliquid-crystal efficiency and the brightness of the display panel whendisplaying images and decrease the brightness non-uniformity to improvethe display quality.

In addition, although the above description merely illustratesembodiments with the pixel electrode having only one finger portion, thepixel electrode may have two or more finger portions as shown in theembodiment of FIG. 4. It should be noted that the exemplary embodimentsshown in FIG. 1A-3D are merely for the purpose of illustration, and theinventive concept may be embodied in various forms without being limitedto the exemplary embodiments.

FIG. 4 is a top view of a pixel electrode of an array substrate inaccordance with another embodiment of the present disclosure. As shownin FIG. 4, the second electrode 108 serving as a pixel electrode mayfurther include a second finger portion 152 substantially parallel tothe first finger portion 116 and a slant slit 154 disposed between thefirst finger portion 116 and the second finger portion 152. The secondelectrode 108 having two finger portions may further increase theliquid-crystal efficiency and the brightness of the display panel whendisplaying images.

In addition, although the above description merely illustratesembodiments with the first electrode being a common electrode and thesecond electrode being a pixel electrode, those skilled in the art willappreciate that the first electrode may be a pixel electrode with thesecond electrode being a common electrode. In other words, in the arraysubstrate, the pixel electrode may be disposed over the substrate andthe common electrode may be disposed over the pixel electrode.

In addition, the present disclosure also provides a display device 200including the aforementioned array substrate 100 as shown in FIG. 5. Thedisplay device 200 in FIG. 5 includes the array substrate 100 of thepresent disclosure, an opposite substrate 202 disposed opposite to thearray substrate 100 and a display medium 204 disposed between the arraysubstrate 100 and the opposite substrate 202.

The opposite substrate 202 may be a color filter substrate, atransparent substrate, or any other suitable substrate. The color filtersubstrate may include a transparent substrate and a color filter layerdisposed over the transparent substrate. The transparent substrate mayinclude, but is not limited to, a glass substrate, a ceramic substrate,a plastic substrate, or any other suitable transparent substrate.

The display medium 204 may be a liquid-crystal material. Theliquid-crystal material may include, but is not limited to, nematicliquid crystal, smectic liquid crystal, cholesteric liquid crystal, bluephase liquid crystal, or any other suitable liquid-crystal material.

The display device 200 may include, but is not limited to, aliquid-crystal display such as a thin film transistor liquid-crystaldisplay. Alternatively, the liquid-crystal display may include, but isnot limited to, a twisted nematic (TN) liquid-crystal display, a supertwisted nematic (STN) liquid-crystal display, a double layer supertwisted nematic (DSTN) liquid-crystal display, a vertical alignment (VA)liquid-crystal display, an in-plane switching (IPS) liquid-crystaldisplay, a cholesteric liquid-crystal display, a blue phaseliquid-crystal display, or any other suitable liquid-crystal display.

In summary, the embodiments of the present disclosure enlarge theconcavity of the pixel electrode at specific side to substantiallyreduce the area of the portion of the connection portion at this side todecrease the amount of the liquid-crystal molecules having the alignmentdirection different from most liquid-crystal molecules at this specificside. Therefore, the liquid-crystal efficiency may be increased, whichin turn increases the brightness of the display panel when displayingimages, and the dark stripes and the bright stripes may be reduced toimprove the display quality.

Although some embodiments of the present disclosure and their advantageshave been described in detail, it should be understood that variouschanges, substitutions and alterations can be made herein withoutdeparting from the spirit and scope of the disclosure as defined by theappended claims. For example, it will be readily understood by thoseskilled in the art that many of the features, functions, processes, andmaterials described herein may be varied while remaining within thescope of the present disclosure. Moreover, the scope of the presentapplication is not intended to be limited to the particular embodimentsof the process, machine, manufacture, composition of matter, means,methods and steps described in the specification. As one of ordinaryskill in the art will readily appreciate from the disclosure of thepresent disclosure, processes, machines, manufacture, compositions ofmatter, means, methods, or steps, presently existing or later to bedeveloped, that perform substantially the same function or achievesubstantially the same result as the corresponding embodiments describedherein may be utilized according to the present disclosure. Accordingly,the appended claims are intended to include within their scope suchprocesses, machines, manufacture, compositions of matter, means,methods, or steps.

What is claimed is:
 1. A display device, comprising: an array substrate, comprising: a substrate; a first electrode disposed over the substrate, wherein the first electrode has an opening and the opening has an edge parallel to a gate-line-extending direction; and a second electrode disposed over the first electrode, wherein the second electrode comprises: a first finger portion having a first outer edge intersecting the gate-line-extending direction at an acute angle to define a first side, and a second outer edge intersecting the gate-line-extending direction at an obtuse angle to define a second side opposite to the first side; and a connection portion connecting the first finger portion at a projection of the edge of the opening projected on the second electrode, wherein the connection portion has a first width along the gate-line-extending direction adjacent to the edge, and the connection portion has a second width along the gate-line-extending direction away from the edge, wherein the first width is smaller than the second width, wherein a part of the connection portion overlapped with the first electrode at the first side is a first region, a part of the connection portion overlapped with the first electrode at the second side is a second region, an area of the first region is smaller than an area of the second region; an opposite substrate; and a display medium disposed between the array substrate and the opposite substrate.
 2. The display device as claimed in claim 1, wherein the connection portion has a first curve at the first side and a second curve at the second side.
 3. The display device as claimed in claim 2, wherein a length of the first curve is greater than a length of the second curve.
 4. The display device as claimed in claim 2, wherein the edge corresponding to an extension line which is parallel to a gate-line-extending direction, the first curve has a first end point away from the edge, and the second curve has a second end point away from the edge, wherein a distance between the first end point and the extension line is greater than a distance between the second end point and the extension line.
 5. The display device as claimed in claim 4, wherein the connection portion has a first margin connecting the first curve at the first side and a second margin connecting the second curve at the second side, wherein with respect to the gate-line-extending direction, an absolute slope value of the first margin is different from that of the second margin.
 6. The display device as claimed in claim 5, wherein the absolute slope value of the first margin is smaller than that of the second margin.
 7. The display device as claimed in claim 5, wherein the first margin has a shorter length than the second margin.
 8. The display device as claimed in claim 5, wherein an angle between the first margin and the gate-line-extending direction is not 90 degrees, and an angle between the second margin and the gate-line-extending direction is not 90 degrees.
 9. The display device as claimed in claim 1, wherein the connection portion has a first inflection point at the first side and a second inflection point at the second side.
 10. The display device as claimed in claim 9, wherein the edge corresponding to an extension line which is parallel to a gate-line-extending direction, in a direction perpendicular to the gate-line-extending direction, a distance between the first inflection point and the extension line is greater than a distance between the second inflection point and the extension line.
 11. The display device as claimed in claim 1, wherein the edge corresponding to an extension line which is parallel to a gate-line-extending direction, the connection portion has a first curve at the first side and a second curve at the second side, in a direction perpendicular to the gate-line-extending direction, a distance between a most-concave point of the first curve and the extension line is greater than a distance between a most-concave point of the second curve and the extension line.
 12. The display device as claimed in claim 1, wherein the second electrode further comprises a second finger portion substantially parallel to the first finger portion.
 13. The display device as claimed in claim 12, wherein the second electrode further comprises a slant slit disposed between the first finger portion and the second finger portion.
 14. The display device as claimed in claim 1, wherein the connection portion further comprises an upper portion adjacent to the edge and a lower portion away from the edge, wherein the upper portion has the first width along the gate-line-extending direction, and the lower portion has the second width along the gate-line-extending direction.
 15. The display device as claimed in claim 14, wherein the connection portion has a first curve at the first side and a second curve at the second side, and the first curve of the connection portion is disposed in the upper portion of the connection portion.
 16. The display device as claimed in claim 14, wherein the connection portion has a first curve at the first side and a second curve at the second side, and the second curve of the connection portion is disposed in the upper portion of the connection portion.
 17. The display device as claimed in claim 14, wherein the connection portion has a first curve at the first side and a second curve at the second side, and the first curve of the connection portion is not disposed in the lower portion of the connection portion.
 18. The display device as claimed in claim 14, wherein the connection portion has a first curve at the first side and a second curve at the second side, and the second curve of the connection portion is not disposed in the lower portion of the connection portion.
 19. The display device as claimed in claim 1, wherein the opening has a first side edge at the first side and a second side edge at the second side, wherein the first region is disposed outside the first side edge at the first side.
 20. The display device as claimed in claim 1, wherein the opening has a first side edge at the first side and a second side edge at the second side, wherein the second region is disposed outside the second side edge at the second side. 